The present invention relates to a foodstuff. More particularly, the present invention relates to a foodstuff comprising at least one functional ingredient which has been generated in situ by a conversion agent.
Traditionally food was prepared in the private households and the constituents of the food or of the foodstuff were brought to the kitchen of the household where the food or foodstuff was prepared shortly before consumption.
Industrial development increased the demand for the reduction of the time and effort required to prepare food or foodstuffs. Thus there has been a massive expansion in the industrial preparation of food.
Recently, there has been increased demand for improvements in the quality of industrially prepared food. In particular there is demand for improved taste, eating quality and shelf life. In an attempt to address these demands for improved foodstuffs, industrial food producers have utilised and have relied upon functional ingredients to meet the demands for quality and shelf life. Functional ingredients such as emulsifiers, hydrocolloids, preservatives, antioxidants, colourings and flavourings are widely used in the food industry.
More recently, there has been demand from consumers to reduce the number of additives, such as functional ingredients, included in foodstuffs. Thus, there is a desire to prepare industrially foodstuffs meeting the quality requirements of consumers whilst minimising the number of additives in the final foodstuffs.
Both Douglas B. Sarney et al., Enzymatic Synthesis of Sorbitan Esters Using a Low-Boiling-Point Azeotrope as Reaction Solvent, Biotechnology and Bioengineering, 1997 vol. 54(4) and J. A. Arcosm et al., Quantitative Enzymatic Production of 6.O-Acylglucose Esters, Biotechnology and Bioengineering 1998 57(5), teach the use lipase for the production of emulsifiers. The teachings require the synthesis of emulsifiers in an organic solvent system. The emulsifier is then isolated from the organic solvent system before use in food.
A. Coteron et al., Reactions of Olive Oil and Glycerol over Immobilised Lipases, JAOCS, Vol. 75, no. 5 (1998) reports the use of immobilised lipase in the reaction of olive oil and glycerol. Subsequent to the reaction the immobilised lipase is removed from the reaction mixture.
JP-A-90188214 reports the use of an immobilised lipase for the hydrolysis and ester exchange of triglyceride. In this process part of the triglyceride is partially hydrolysed to free fatty acid. The partially hydrolysed triglyceride product is used for production of margarine.
U.S. Pat. No. 5,288,619 relates to enzymatic methods for the production of oils or fats having a specific fatty acid profile. In particular, U.S. Pat. No. 5,288,619 discloses the use of a lipase to transesterification two oils or fats. A particularly preferred embodiment of this document uses an immobilised lipase. The resultant oils or fats, the required specific fatty acid profile, may subsequently be incorporated in a foodstuff or food material. For example the transesterified oils/fats may be incorporated in a margarine recipe.
U.S. Pat. No. 4,865,866 teaches the use of a lipase to rearrange by transesterification the fatty acids components of a fat/oil. The disclosed lipases are immobilised, for example by support on Celite. The process is performed to provide a fat/oil composition having a specific fatty acid distribution. The fat/oil composition obtained by the transesterification may be incorporated in a foodstuff such as a plastic emulsion product e.g. a margarine or low fat spread.
JP-A-5211852 discloses the addition of a lipase to a mixture of water and less than 30% oil. The product prepared in this method may be used in the production of mayonnaise. The mayonnaise is prepared at a temperature such that the activity of lipase is not reduced. In the procedure of JP-A-5211852 the oil is degraded to free fatty acid or fatty acid salts(soap) and glycerol which may provide the emulsifying properties. However, this may be problematic as the emulsification properties of this reaction product will depend on the pH of the mixture. This is because the effect of fatty acid is pH dependent. At low pH free fatty acid is present in the acid form which has low emulsification properties. At alkaline pH however free fatty acid is available as a soap, which is known to have good emulsification properties. For the production of a creamy substance described in JP-A-5211852 this may not be a problem. However, for other foodstuffs this may be a problem. For example, in margarine production pH is adjusted to 4.5 or 5.5 or other pH values depending on the recipe. In this case the effect of free fatty acid formation by the lipase will impact on the emulsification of the foodstuff.
The present invention addresses the problem of the prior art.